Bangka Belitung faces very serious environmental problems due to illegal tin mining that give negative impacts to the sustainability of ecosystem and human life. Bangka Belitung is the second largest producer of tin in the world and tin mining in Bangka Belitung has been exploited since long time ago (hundred years). Tin mining activity basically increase the wealth of the community but it decrease the environmental stability inshore & offshore.  Taking a case study approach, this study will be conducted this month by reviewing and analyzing various legal instrument (primary & secondary data) related to tin mining & environmental problem. Beside that, this study addresses the following research questions : What is the backround issues relating the case between tin mining and environmental degradation in Bangka Belitung? How do tin mining activity (upstream & downstream system) give influence to this environmental degradation? What is the relationship between the law enforcement and the social system in  tin mining issue?  Another important point is how then the concreteness of law enforcement regarding environmental policy in tin mining issue can be applied in the right way and the right system can support the implementation of SDGs (Sustainable Development Goals) to take care of environment for our future in Indonesia especially in Bangka Belitung.